#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#include<algorithm>
#define debug(a) cout<<#a<<"="<<a<<endl;
using namespace std;
const int maxn=2e5+1000;
typedef long long LL;
inline LL read(){LL x=0,f=1;char ch=getchar();	while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
return x*f;}
int main(void){
   cin.tie(0);std::ios::sync_with_stdio(false);
   LL n,k;cin>>n>>k;
   while(1){
      for(LL i=0;i<k;i++){
          for(LL j=i;j<k;j++){
              cout<<(char)('a'+i);n--;
              if(n==0) return 0;
              if(j!=i){
                cout<<(char)('a'+j);n--;
                if(n==0) return 0;
              }
          }
      }
   }
   return 0;
}
